Objectives
Our research determined 1) how phonological priming of picture naming
was affected by the mode (auditory-visual [AV] vs auditory), fidelity
(intact vs non-intact auditory onsets), and lexical status (words vs
nonwords) of speech stimuli in children with prelingual sensorineural
hearing impairment (CHI) vs. children with normal hearing (CNH); and 2) how
the degree of hearing impairment (HI), auditory word recognition, and age
influenced results in CHI. Note that some of our AV stimuli were not the
traditional bimodal input but instead they consisted of an intact
consonant/rhyme in the visual track coupled to a non-intact onset/rhyme in
the auditory track. Example stimuli for the word bag are:
1) AV: intact visual (b/ag) coupled to non-intact auditory
(−b/ag) and 2) Auditory: static face coupled to
the same non-intact auditory (−b/ag). Our question
was whether the intact visual speech would “restore or
fill-in” the non-intact auditory speech in which case performance
for the same auditory stimulus would
differ depending upon the presence/absence of visual
speech.
Design
Participants were 62 CHI and 62 CNH whose ages had a group-mean and
-distribution akin to that in the CHI group. Ages ranged from 4 to 14 years.
All participants met the following criteria: 1) spoke English as a native
language, 2) communicated successfully aurally/orally, and 3) had no
diagnosed or suspected disabilities other than HI and its accompanying
verbal problems. The phonological priming of picture naming was assessed
with the multi-modal picture word task.
Results
Both CHI and CNH showed greater phonological priming from high than
low fidelity stimuli and from AV than auditory speech. These overall
fidelity and mode effects did not differ in the CHI vs. CNH—thus
these CHI appeared to have sufficiently well specified phonological onset
representations to support priming and visual speech did not appear to be a
disproportionately important source of the CHI’s phonological
knowledge. Two exceptions occurred, however.
First—with regard to lexical status—both
the CHI and CNH showed significantly greater phonological priming from the
nonwords than words, a pattern consistent with the prediction that children
are more aware of phonetics-phonology content for nonwords. This overall
pattern of similarity between the groups was qualified by the finding that
CHI showed more nearly equal priming by the high vs. low fidelity nonwords
than the CNH; in other words, the CHI were less affected by the fidelity of
the auditory input for nonwords. Second, auditory word
recognition—but not degree of HI or age—uniquely influenced
phonological priming by the nonwords presented AV.
Conclusions
With minor exceptions, phonological priming in CHI and CNH showed
more similarities than differences. Importantly, we documented that the
addition of visual speech significantly increased phonological priming in
both groups. Clinically these data support intervention programs that view
visual speech as a powerful asset for developing spoken language in C...